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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        //1、BigInt
        const bigNum = BigInt('124513453211215645564516544451563561564566565')
        console.log('bigNum',bigNum)

        //2、 引入 decimal.js

        //3 表单校验，禁止输入超过18位的数字
    </script>
</body>
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